Joseph corbett



2 Sheets- Sheet l.

(No Model.)

JJCORBETT.A I

LOGK.-

No. 424,859. Patented Apr. l. 1890.

` ATTORNEY N. Pneus mwumamphnr. wamingum. D n

2 Sheets-Sheet 2 (No Model.)

J. CORBETT..

LOCK.

No. 424,859. Patented Apr. l, 1890.

INVENTOR A TToRNEY UNITED STATES ATENT OFFICE.

JOSEPH CORBETT, OF NE YORK, N. Y., ASSIGNOR OF ONE-HALF TO THOMAS F.SI-IAV AND HENRY M. IVOOLF, OF SAME PLAGE.

LOCK.

SPECIFICATION forming part of Letters Patent No. 424,859, dated April 1,1890.

Application led February 23, 1889. Serial No. 300,868. (No model.)

To a/ZZ whom t may concern:

Be it known that I, JOSEPH CORBETT, a citizen of the United States, anda resident of New York city, in the county of New York and State of NewYork, have invented certain new and useful Improvements in Locks, ofwhich the following is a speciication.

My invention relates to new and useful features in letter or like boxes;and it consists in improvements in the lock and door of the box wherebythe following advantages are secured: First, it is impossible for thepostman to leave the box before the door thereof is closed; second, itis very difficult to pick the lock of the door third, a differentshapedkey from any now in use for lettenboXes or other purposes, so far as Iam informed, is used; fourth, the device for relooking of the box isautomatic.

By my invention also I secure by means of an index a registration of thenumber of times the letter-box has been opened, and I can also givenotice on the box of the next time it will be opened.

In the drawings the same reference-letters indicate the same parts inall the figures.

Figure l illustrates a side view of the letter-box, a portion of itbeing in section. Fig. 2 illustrates a front view of the lock, ease, andindex, a part of the faceplate being broken away to show the lockmechanism behind it,l

the lock being unlocked. Fig. 3 illustrates a View similar to that shownin Fig. 2, the lock being locked. Figs. 4t and 5 illustrate perspectiveviews showing the engagement of the lock-bolt with the door of the box.Fig. 6 illustrates the bolt and coacting parts separate from thetumbler, dsc. Figs. 7 and S illustrate the key.

A is the boX. It is Triade of such material and of such form aspreferred.

Bis the door through which the contents are withdrawn.

Gis a loclecase attached to the inside of the box adjacent to thedoor-opening. The lock mechanism comprises a bolt D, which is providedwith a felice E, rigidly fastened to one side thereof.

F is a pin or its equivalent, which works in a slot G in the bolt.

II is a spring which is attached to the case of the look by means of astud I, the free end whereof is attached to the bolt at .I and normallythrows the bolt forward into its locked position. (Seen in Fig. 3.) Thebolt D is provided with an enlargement or wing K, which projects fromthe side of the lock-case. It is in the present case what may be termedt-he locking-surface of the bolt; but it may be otherwise disposed thanas here shown. Then the bolt is retracted by the key, this projection K,or some other suitable part of the bolt, engages with a spring-pawl L,which is at tached at M to the lock-casing or other equiva lent lixedpart, thus holding the bolt in its retracted position until the door isagain closed. The spring-pawl L, as shown in Fig. fi, is located in thepath of the locking-piece N of the door. Thus when the door is closedthe locking-piece N strikes the spring-pawl L and presses it inwardlyaway from its en gagement with the bolt, and the bolt then, under theaction of the spring II, instantly shoots forwardly, passing behind thelocking-piece N of the door, and again locks the door.

O is a spring-pawl. It is pivoted to the lock-bolt D at l and isprovided with a spring` Q. This pawl engages with the teeth of aratchet-wheel R, which is attached to the back side of an index-plate S,which carries on its exposed face such figures or other indicia as maybe desired, which are observable through an aperture T, (one or more,)made in the front of the box.

V is a plate of glass, which is fastened ina suitable frame-work of thebox U, whereby the index may be read, anddust, the., )revented. fromgetting tothe lock or index mechanism.

IV is a spring or gravity stoppawl, (shown herein as spring-actuated,)which takes up the movement of the index and prevents backward turningthereof when the spring-pawl O is retracted by the forward movement ofthe bolt.

X is a lock-tumbler somewhat similar to those used in the well-knownYale and other locksthat is to say, it is provided with a spring Y,whereby it is normally held in an elevated position, and it has also arecess Z, into which the fence E moves when the tumbler is brought intoproper position for such movement. It is also preferably provided withfalse notches Z, to render picking practically impossible.

I illustrate but one tumbler; but I wish it to be understood that, ifdesired, for the purposes of greater security or for other reasons, asmany tumblers as desired may be used, they all being brought into properposition relative to the fence E by means of the elevations anddepressions on the key, as now well understood.

A', Figs. 7 and S, is the key. Itis composed of a piece of angle metal,preferably steel. On one part a, which I will call the horizon-y talsection, there isformed a single cam-surface b, which is so located onthe said horizontal section as that when the elevations and depressionson the other part of the key c, which I will call the vertical section,has brought the recesses Z of all the tumblers in line with the fence Ethat it (the cam-surface b) will press the bolt rearwardly by its im`pact against the rear edge CZ of an opening e made in the bolt, throughwhich the key passes. It will thus be seen that the location of thiscam-surface on the horizontal section will be determined by the numberof tum` blers used in the lock.

In order that it may be impossible to withdraw the key from the lockafter the lock has been unlocked without again locking the door, Iprovide on the forward end of the key an upwardly extending spur f,which, as shown in Figs. 6, 7, and 8, is covered bya part g of the boltD when it is passed so far rearwardly as to engage with the spring-stoppawl L, the adjustment being such that the lock is not unlocked untilthis takes place. Thus the .key can be moved outwardly for the purposeof allowing forward movement of the bolt when the spring-pawl L istripped by the closing of the door; but it cannotbe removed from thelock until the door is closed and locked.

The operation of this apparatus has been so fully described already thatdetailed description of the movements of the parts will not benecessary. Generally stated, however, the operation .is as follows: Theoperator presses the key inwardly. This act iirst depresses thetumblers, and,second, presses the bolt rearwardly, the fence E passinginto the recesses Z in the tumblers, and the bolt is held in itsrearward position by the springpawl L. The door, being now unlocked, is

moved slightly open by the pressure of the spring-pawl L, and it then byitself drops fully opened, by'reason of the hinge being out of thecentral line of gravity. This being done and the mail removed, theoperator closes the door again, and the locking-piece N thereof or itsequivalent, striking the spring stop-pawl L, liberates the bolt, whichat once shoots forwardly, locking the door and liberating the key, whichis then withdrawn by the operator, who proceeds upon his Way. The springH, as soon Vas the spring-pawl L is tripped by the closing of the door,presses the key outwardly by reason of the impact of the bolt againstthe camsurface bthereof, thus allowing the bolt to lock.

It will be noticed that when my lock is locked it becomes a dead-lock,so calledthat is to say, the bolt cannot be sprungback until thetumblers are again rendered coincident with the fence. I call attention,also, to the fact that the point of contact between thetumbler-actuating part of my key and the tumblers is much nearer thepivot of the tumblers than heretofore. Thus I multiply the movementnecessary to bring the recesses Z coincident with the fence E, thusgreatly increasing the difficulty of picking the lock. Each unlocking ofthe boX makes a register of' such kind as may be desired on the index,

depending on the charater of the indicia on the face of the dial.

I do not limit myself to the details of construction shown. It isobvious that many minor alterations may be made therein and still thespirit of my invention be used.

Having described my invention, I claim l. The combination of a lockhaving a springactuated bolt, a stop-pawl which engages with the boltand holds it when in its unlocked position, said pawl being tripped bythe door when reclosed, an index operated by the movement of the bolt,and a shoulder on the key which engages with .the bolt when in itsunlocked position, whereby the key cannot be removed from the lock untilthe bolt is again brought to its locked position, substantially as setforth.

2. The combination of a lock having a spring-actuated bolt, a stop-pawlwhich engages with the bolt and holds it when in its unlocked position,said pawl being tripped by the door when reclosed, and an index operatedby the movement of the bolt, substantially as set forth.

3. The combination of a lock having a spring-actuated bolt, a stop-pawlwhich engages with the bolt and holdsl it when in its unlocked position,said pawl being tripped by the door when reclosed, and a key having ashoulder thereon which engages with the bolt when in its unlockedposition, whereby the key cannot be removed from the lock until the boltis again brought to its locked position, substantially as set forth.

4. A lock provided with tumblers and a spring-actuated bolt, and a keyhaving two parts at substantially right angles toeach other, one ofwhich parts actuates the tumblers and the other retraots the bolts atthe same inward movement of the key and without turning it.

5. A lock provided with tumblers and a IOO spring-actuated bolt, and akey having two parts at substaniially right angles to each other, one ofwhich aotuates the tumblers and the other retraets the bolt at the sameinward movement of the key, the bolt being held against endWise pressureby the tumbler when locked, substantially as set forth.V

Signed at New York, in the county of N ew York and State of New York,this 11th clay of February, A. D. 1889.

JOSEPH CORBETT.

Witnesses:

PHrLLiPs ABBOTT, D. S. RITTERBAND.

